4-Way Trailer Wiring Harness – Heavy-Duty 18 AWG Copper Wiring

Reliable Trailer Wiring for Long-Lasting Performance

Keep your trailer's lighting system connected with the Connective Solutions Group 4-Way Trailer Wiring Harness. Designed for dependable performance, this heavy-duty harness features color-coded copper wiring, a durable molded 4-pin flat connector, and protective cable insulation.

Available in multiple lengths to accommodate a variety of trailer sizes and wiring requirements.

Premium Copper Construction

Manufactured with 18 AWG, 100% pure stranded copper conductors for excellent electrical conductivity, flexibility, and dependable performance. Unlike copper-clad aluminum (CCA) wiring, pure copper provides reliable conductivity and durability for demanding trailer applications.

Each conductor is insulated with durable PVC to help protect against abrasion, everyday wear, and environmental exposure. The flexible stranded construction is designed to withstand the movement and vibrations commonly experienced during trailer operation, providing a long-lasting wiring solution for boat, utility, cargo, and other trailers.

Heavy-Duty 4-Way Flat Connector

The molded 4-pin trailer-side connector is designed to fit industry-standard 4-way flat connections. Its one-piece construction helps protect the electrical connection from moisture, corrosion, and everyday wear.

The first 48 inches of wiring are enclosed in a protective jacket for additional durability near the trailer tongue.

Wishbone-Style Wiring Configuration

Designed with five color-coded wires that separate along both sides of the trailer for convenient installation:

• White: Ground (negative)

• Brown (2 wires): Tail and running lights

• Yellow: Left turn signal and brake light

• Green: Right turn signal and brake light

The wishbone configuration allows the wiring to run along both sides of the trailer without requiring additional splices for the running lights.

Versatile Trailer Compatibility

Suitable for a variety of trailer applications, including boat trailers, utility trailers, cargo trailers, ATV trailers, and horse trailers.

Designed for conventional 4-way trailer lighting systems. Not intended for trailer braking systems requiring additional electrical circuits.

Product Specifications

• Connector: 4-Way Flat, Trailer-Side

• Wire Gauge: 18 AWG

• Conductor Material: Stranded Oxygen-Free Copper

• Wire Configuration: 5-Wire Wishbone Style

• Insulation: PVC

• Protective Jacket: First 48 inches

• Voltage Rating: 300V

• Temperature Rating: -22°F to 221°F

• Available Lengths: 17 FT, 20 FT, 25 FT, 30 FT, 35 FT, 40 FT, and 45 FT

Select your preferred harness length from the options above.

Custom Wiring Solutions

Need a different length, connector configuration, or bulk quantity? Connective Solutions Group offers custom wiring harness solutions for trailer manufacturers and businesses.

Contact us to discuss your requirements and request a quote.